[PATCH 13/22 v4] Input: atmel_mxt_ts - read ID information block in one i2c transaction

From: Daniel Kurtz
Date: Mon Jun 18 2012 - 00:12:17 EST


Reading the whole info block in one i2c transaction speeds up driver
probe significantly, especially on slower i2c busses.

Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
---
drivers/input/touchscreen/atmel_mxt_ts.c | 26 +++-----------------------
1 files changed, 3 insertions(+), 23 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index efce50f..87004ec 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -36,6 +36,7 @@
#define MXT_FW_NAME "maxtouch.fw"

/* Registers */
+#define MXT_INFO 0x00
#define MXT_FAMILY_ID 0x00
#define MXT_VARIANT_ID 0x01
#define MXT_VERSION 0x02
@@ -758,32 +759,11 @@ static int mxt_get_info(struct mxt_data *data)
struct i2c_client *client = data->client;
struct mxt_info *info = &data->info;
int error;
- u8 val;
-
- error = mxt_read_reg(client, MXT_FAMILY_ID, &val);
- if (error)
- return error;
- info->family_id = val;
-
- error = mxt_read_reg(client, MXT_VARIANT_ID, &val);
- if (error)
- return error;
- info->variant_id = val;
-
- error = mxt_read_reg(client, MXT_VERSION, &val);
- if (error)
- return error;
- info->version = val;
-
- error = mxt_read_reg(client, MXT_BUILD, &val);
- if (error)
- return error;
- info->build = val;

- error = mxt_read_reg(client, MXT_OBJECT_NUM, &val);
+ /* Read 7-byte info block starting at address 0 */
+ error = __mxt_read_reg(client, MXT_INFO, sizeof(*info), info);
if (error)
return error;
- info->object_num = val;

return 0;
}
--
1.7.7.3

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